BACKGROUND: Rosmarinic acid (RA) is a polyphenol found in various plants, especially in the Lamiaceae family, such as rosemary, sage, lemon balm, and basil, and especially in peppermint. Mitochondria have cell-type-specific phenotypes, perform dozens of interconnected functions, and undergo dynamic and often reversible physiological recalibrations. One of the main current goals is to enhance mitochondrial function through various strategies, including nutritional ones.
METHODOLOGY: Mouse muscle cells (C2C12) were differentiated and treated with RA. Mitochondrial genes were measured by RT-qPCR, and proteins by Western blotting. Mitochondrial respiration was measured using Seahorse XF and Oroboros O2k. Mitochondrial biogenesis was analyzed by citrate synthase activity, and finally, the antioxidant role was observed by hydrogen peroxide production, catalase activity, and malondialdehyde (MDA) levels using HPLC.
RESULTS: Mitochondrial genes were overexpressed compared to the control group using AR. Both basal and maximal respiration, including ATP production, were higher with AR exposure. There was increased activity of the citrate synthase enzyme and proteins such as PGC-1α and TFAM related to mitochondrial biogenesis. There was increased catalase activity, lower hydrogen peroxide levels, and lower MDA levels.
CONCLUSIONS: AR at nutritionally relevant doses (100 nM) increases mitochondrial function, both in respiration and mitochondrial biogenesis, and acts as an antioxidant in differentiated mouse muscle cells.